Final portion of the fix for bug 20882. Just a cleaner way of doing what is already being done.

js/src/jsprf.c

@@ -50,11 +50,11 @@
 ** Note: on some platforms va_list is defined as an array,
 ** and requires array notation.
 */
-#if (defined(linux) && defined(__powerpc__)) || (defined(__QNX__) && !defined(NTO)) || defined(WIN16)
+#ifdef HAVE_VA_LIST_AS_ARRAY
 #define VARARGS_ASSIGN(foo, bar)	foo[0] = bar[0]
 #else
 #define VARARGS_ASSIGN(foo, bar)	(foo) = (bar)
-#endif /* Linux/PPC || WIN16 */
+#endif
 
 /*
 ** WARNING: This code may *NOT* call JS_LOG (because JS_LOG calls it)

js/src/xpconnect/src/xpcconvert.cpp

@@ -932,7 +932,7 @@ XPCConvert::JSErrorToXPCException(JSContext* cx,
 ** Note: on some platforms va_list is defined as an array,
 ** and requires array notation.
 */
-#if (defined(linux) && defined(__powerpc__)) || (defined(__QNX__) && !defined(NTO)) || defined(WIN16)
+#ifdef HAVE_VA_LIST_AS_ARRAY
 #define VARARGS_ASSIGN(foo, bar)	foo[0] = bar[0]
 #else
 #define VARARGS_ASSIGN(foo, bar)	(foo) = (bar)

xpcom/ds/nsTextFormater.cpp

@@ -41,8 +41,7 @@
 ** Note: on some platforms va_list is defined as an array,
 ** and requires array notation.
 */
-#if (defined(LINUX) && defined(__powerpc__)) || defined(WIN16) || \
-    defined(QNX) || (defined(__NetBSD__) && defined(__powerpc__))
+#ifdef HAVE_VA_LIST_AS_ARRAY
 #define VARARGS_ASSIGN(foo, bar)	foo[0] = bar[0]
 #else
 #define VARARGS_ASSIGN(foo, bar)	(foo) = (bar)